In the data-processing and space sectors, contractual engineering has been used to adapt the law to the specificity and complexity of the aforesaid activities. This results in an important cooperation of the co-contracting parties, which is absolutely necessary. This also results in consequences regarding the intensity of the parties' obligations, often regarded as obligations of means because of the risk of the activities in question, and regarding the careful drafting of the clauses limiting the liability of the co-contracting parties.